The disclosure of the present disclosure relates to damper devices including an input element to which power from an internal combustion engine is transmitted, and an output element.
Conventionally, a double path damper that is used in association with a torque converter is known as this type of damper devices (see, e.g., Published Japanese Translation of PCT Application No. 2012-506006). In this damper device, a vibration path from an engine and a lockup clutch to an output hub is divided into two parallel vibration paths B, C, and each of the two vibration paths B, C includes a pair of springs and a separate intermediate flange placed between the pair of springs. A turbine of a torque converter is connected to the intermediate flange of the vibration path B so that the resonant frequency varies between the two vibration paths. The natural frequency of the intermediate flange in the vibration path B is lower than that of the intermediate flange in the vibration path C. When the lockup clutch is engaged, engine vibration enters the two vibration paths B, C of the damper device. When the engine vibration having a certain frequency reaches the vibration path B including the intermediate flange connected to the turbine, the phase of the vibration from the intermediate flange to the output hub in the vibration path Bis shifted by 180 degrees with respect to that of the input vibration. Since the natural frequency of the intermediate flange in the vibration path C is higher than that of the intermediate flange in the vibration path B, the vibration having entered the vibration path C is transmitted to the output huh without any phase shift. The vibration transmitted to the output hub through the vibration path B is thus 180 degrees out of phase with respect to that transmitted to the output hub through the vibration path C, whereby damped vibration can be obtained at the output hub.